叶片丢失激励下航空发动机柔性转子系统的动力学响应

Dynamic response of the aero-engine flexible rotor system under the blade-off

为揭示叶片丢失激励下转子系统动力学响应特征,考虑涡扇发动机低压转子刚度/质量分布特征、载荷传递特征、转静件耦合特征等,建立了高速柔性悬臂转子系统动力学模型。对突加不平衡激励及持续碰摩约束下转子系统动力学响应特性进行分析。结果表明:所建立转子动力学模型可以有效反映叶片丢失激励下转子冲击振动和复杂简谐振动响应特征。在突加不平衡激励下转子系统的瞬态振动响应加剧,具有显著冲击响应特征,并伴有转子横向固有振动。持续碰摩所产生的约束作用可使转子临界转速发生变化,虽然响应幅值降低,但频率成分及转子振动趋于复杂。

To reveal the dynamic response characteristics of the rotor under the bladeoff,the dynamic model of the flexible cantilever rotor system was established,by considering the distribution characteristics of the stiffness and mass,the load transfer,as well as the rotor/stator coupling of the low pressure rotor in turbofan engine.The dynamic response characteristics of the rotor system under sudden unbalance excitation and continuous rub-impact constraint were analyzed.The results showed that,the established rotor dynamic model can effectively reflect the rotor vibration under the blade-off and the complex harmonic vibration response characteristics.The transient response of the rotor under the sudden unbalance excitation was aggravated,and the impact response characteristics were showed.The critical speed of rotor increased under the continuous rub-impact,while the amplitude of response decreased,and the frequency components and rotor vibration were inclined to be complex.